I'm doing a Huge landscaping job at this 1 acre property I bought a couple of years ago. One section of about 1/3 acre is going to be a wildlife garden. It will have a pond, grassland, Aspen Grove and a few streams as part of the layout. Another section of about 1/2 acre is going to be a small orchard, a berry patch, vegetable garden and then large winding flower beds.
I want to document the changes and growth of both sections with photos but also with time lapse movies eventually. I want to set up a cameras on poles maybe 20' or so high off the ground. One or two for the back garden and one for the front garden. I'd like the cameras to take One to three photos a day 365 days a year for the next 3-5 years.
My question is what would be the best camera for such a job? I can build a small enclosure around the camera but it'd still have to be pretty rugged I'd imagine. I can run power to them and I have a spare iMac that can be used to have photos downloaded to instead of using in camera memory. HDR would be a huge plus as would RAW but size might be a constraint there. I do need to keep costs down so expense is a major factor.

Any ideas would be helpful and any links to info on projects such as this would be appreciated.